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1.
J Dent Res ; : 220345241256618, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38910411

RESUMO

After nasal bone fractures, fractures of the mandible are the most frequently encountered injuries of the facial skeleton. Accurate identification of fracture locations is critical for effectively managing these injuries. To address this need, JawFracNet, an innovative artificial intelligence method, has been developed to enable automated detection of mandibular fractures in cone-beam computed tomography (CBCT) scans. JawFracNet employs a 3-stage neural network model that processes 3-dimensional patches from a CBCT scan. Stage 1 predicts a segmentation mask of the mandible in a patch, which is subsequently used in stage 2 to predict a segmentation of the fractures and in stage 3 to classify whether the patch contains any fracture. The final output of JawFracNet is the fracture segmentation of the entire scan, obtained by aggregating and unifying voxel-level and patch-level predictions. A total of 164 CBCT scans without mandibular fractures and 171 CBCT scans with mandibular fractures were included in this study. Evaluation of JawFracNet demonstrated a precision of 0.978 and a sensitivity of 0.956 in detecting mandibular fractures. The current study proposes the first benchmark for mandibular fracture detection in CBCT scans. Straightforward replication is promoted by publicly sharing the code and providing access to JawFracNet on grand-challenge.org.

2.
Br J Oral Maxillofac Surg ; 57(5): 397-406, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31076220

RESUMO

The aim of this systematic review (for which we followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines) was to provide an overview of the protocols and clinical outcomes of dental implants placed in growing jaws. We searched the MEDLINE/PubMed, Embase, Scopus, and Science Direct databases in October and November, 2017. A total of 3492 studies were identified, and all the studies reporting the outcomes of dental implants placed during the growth phase were included in the study. After duplicates had been removed, 2133 studies were screened based on their titles and abstracts, and 162 were selected for reading. Finally, 28 studies were included in the review. Overall, 493 dental implants were placed in 147 patients aged from 3-18 years old with follow-up being from 1-20 years. The most common disorders seen that were associated with missing teeth were ectodermal dysplasia and dental trauma. The main complications reported were the infraocclusion positioning of dental implants in the maxillary arch and the rotation of dental implants in the mandibular arch. Dental implants were indicated for the anterior regions of the maxilla and mandible in patients over 10 years old, and placement of maxillary implants in a more coronal position was recommended. Consultations and adjustments to prostheses were required until growth had ceased. In growing jaws, dental implants require positional modifications, and they should be considered only under special circumstances.


Assuntos
Implantação Dentária Endóssea/métodos , Implantes Dentários , Mandíbula/crescimento & desenvolvimento , Maxila/crescimento & desenvolvimento , Adolescente , Anodontia , Criança , Pré-Escolar , Prótese Dentária Fixada por Implante , Humanos , Desenvolvimento Maxilofacial/fisiologia
3.
Int J Oral Maxillofac Surg ; 46(12): 1641-1649, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28641898

RESUMO

Sclerosing odontogenic carcinoma (SOC) is a primary intraosseous carcinoma of the jaws that has been listed as a separate entity for the first time in the latest version of the World Health Organization classification of Head and Neck Tumours (2017). The aim of this study was to analyse and interpret the existing literature on SOC in the context of a clinical case treated in the authors' department. A systematic search of the PubMed database was performed in accordance with the PRISMA guidelines, yielding nine cases of SOC reported so far. In summary, characteristic clinical and radiological features of SOC include asymptomatic swelling, location predominantly in the mandible, tumour primarily lytic in appearance, presence of cortical bone destruction, and lack of metastatic spread. Due to the rarity of the disease, close collaboration between oral/maxillofacial surgeons and pathologists is crucial to avoid misdiagnosis. With complete excision, no recurrence of SOC should be expected.


Assuntos
Carcinoma/diagnóstico por imagem , Carcinoma/patologia , Carcinoma/cirurgia , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Tumores Odontogênicos/diagnóstico por imagem , Tumores Odontogênicos/patologia , Tumores Odontogênicos/cirurgia , Humanos , Organização Mundial da Saúde
4.
Br J Oral Maxillofac Surg ; 55(5): 500-503, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28238524

RESUMO

The aim of this working group was to establish a ROMSE (recording of orofacial manifestations in people with rare diseases) database to provide clinicians, patients, and their families with better information about these diseases. In 2011, we began to search the databases Orphanet, OMIM® (Online Mendelian Inheritance in Man®), and PubMed, for rare diseases with orofacial symptoms, and since 2013, the collected information has been incorporated into a web-based, freely accessible database. To date, 471 rare diseases with orofacial signs have been listed on ROMSE, and 10 main categories with 99 subcategories of signs such as different types of dental anomalies, changes in the oral mucosa, dysgnathia, and orofacial clefts, have been defined. The database provides a platform for general clinicians, orthodontists, and oral and maxillofacial surgeons to work on the best treatments.


Assuntos
Bases de Dados Factuais , Vigilância da População , Doenças Raras/epidemiologia , Doenças Estomatognáticas/epidemiologia , Humanos , Internet , Software
5.
Nanotechnology ; 24(11): 115604, 2013 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-23449006

RESUMO

The current work presents a one-step procedure for the synthesis of amphiphilic silver nanoparticles suitable for production of silver-filled polymeric materials. This solvent free synthesis via reduction of Tollens' reagent as silver precursor in melts of amphiphilic polyesters consisting of hydrophilic poly(ethylene glycol) blocks and hydrophobic alkyl chains allows the production of silver nanoparticles without any by-product formation. This makes them especially interesting for the production of medical devices with antimicrobial properties. In this article the influences of the chain length of the hydrophobic block in the amphiphilic polyesters and the process temperature on the particle size distribution (PSD) and the stability of the particles against agglomeration are discussed. According to the results of spectroscopic and viscosimetric investigations the silver precursor is reduced to elemental silver nanoparticles by a single electron transfer process from the poly(ethylene glycol) chain to the silver ion.

6.
Leukemia ; 19(10): 1745-50, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16107886

RESUMO

Infectious complications represent a substantial cause of morbidity and mortality in children undergoing therapy for acute myeloid leukemia (AML). Since it has been shown that alterations in innate immune pathways contribute to the risk for serious infections, we analyzed well-characterized variants in innate immune genes (TNF, IL6, IL8, MPO, CHIT, FCGR2A, TLR2, and TLR4) to determine their possible contribution to infectious complications during therapy for pediatric AML. The study population consisted of 168 North European Caucasian children enrolled on the clinical trial AML-BFM 93. We found an association between Gram-negative bacterial infection and common, functional variants in two genes, IL6 and CHIT. The risk for infection was significantly higher in children with the G allele in the IL6 promoter at -174 bp (P=0.026) and in patients with the H allele of CHIT (P=0.033). The promoter variant in IL6 has been shown to increase expression while the H allele disrupts both function and circulating levels. Our data suggest that variant alleles of both IL6 and CHIT could influence susceptibility to infection with Gram-negative bacteria in children undergoing therapy for AML. Follow-up studies, namely replication association studies and in vitro investigation of these common polymorphisms, are warranted to confirm these observations.


Assuntos
Infecções por Bactérias Gram-Negativas/etiologia , Hexosaminidases/genética , Interleucina-6/genética , Leucemia Mieloide/genética , Polimorfismo Genético , Regiões Promotoras Genéticas/genética , Doença Aguda , Adolescente , Alelos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Feminino , Variação Genética , Genótipo , Bactérias Gram-Negativas/isolamento & purificação , Hexosaminidases/sangue , Humanos , Lactente , Recém-Nascido , Interleucina-6/sangue , Leucemia Mieloide/tratamento farmacológico , Leucemia Mieloide/microbiologia , Masculino
7.
J Neurosurg Anesthesiol ; 11(2): 112-8, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10213438

RESUMO

The effects of the opioids fentanyl, alfentanil, and sufentanil on motor pathways were studied in a total of 30 rabbits. Compound muscle action potentials (CMAP) were recorded from the extensor muscles of the upper extremity as well as evoked spinal cord potentials (ESCP) from the thoracic epidural space in response to electrical stimulation of the motor cortex. After establishing stable baseline values, an equipotent intravenous bolus of one of the three opioids was applied that abolished reflex motor response to noxious stimulation. Motor evoked potentials (MEP) were recorded from the time of bolus administration until recovery of MEP amplitudes and latencies. Afterwards, the opioids were administered continuously with cumulative dosage up to total absence of motor evoked response. Our results show a dose-dependent suppression of the CMAP: When reflex movement to noxious stimulation was extinguished, we found a significant (P < .001) reduction of the amplitudes to 34+/-18% (mean +/- SD) in the fentanyl group, to 43+/-24% in the alfentanil group, and to 53+/-20% of baseline values in the sufentanil group. Increasing opioid plasma levels were associated with complete extinction of the CMAP. We hypothesize that the descending volleys within motor pathways are mainly inhibited at a spinal level, because ESCP, particularly the number of spinal I-waves, are not severely affected even when CMAP are completely suppressed. In conclusion, intraoperative monitoring of descending pathways by means of MEP during anesthesia with opioids is feasible at anesthetic plasma concentrations maintaining a surgical level of analgesia. Even with high opioid plasma levels, a valid MEP monitoring could be performed evaluating neural activity of spinal MEP.


Assuntos
Potenciais de Ação/fisiologia , Alfentanil/farmacologia , Potencial Evocado Motor/efeitos dos fármacos , Fentanila/farmacologia , Córtex Motor/fisiologia , Músculo Esquelético/fisiologia , Medula Espinal/fisiologia , Sufentanil/farmacologia , Potenciais de Ação/efeitos dos fármacos , Anestesia Intravenosa , Anestésicos Intravenosos/farmacologia , Animais , Estimulação Elétrica , Masculino , Monitorização Intraoperatória , Atividade Motora , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/inervação , Coelhos , Tempo de Reação , Reflexo , Medula Espinal/efeitos dos fármacos
8.
Clin Chem ; 44(7): 1459-65, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9665424

RESUMO

A time-consuming sample preparation and measuring procedure is required for the quantitation of retinyl palmitate by HPLC. We developed a fluorometric method for the determination of total retinyl esters in chylomicrons, chylomicron remnants, and VLDL. This method is precise, sensitive, rapid, simple, and particularly useful for large-scale studies of postprandial lipid metabolism. Because the turbidity of postprandial lipemic samples interferes with the fluorescence measurement, all samples were incubated for 10 min with a clearing buffer containing esterase and detergents. This buffer eliminates the turbidity and hydrolyzes all retinyl esters to retinol. The fluorescence signal (excitation wavelength, 330 nm; emission wavelength, 490 nm) was linear from 0.1 mg/L up to 4 mg/L retinyl palmitate, and the CVs were 3.6% within-run and 5.1% within-series. A first application studied postprandial lipoproteins, which were first separated by ultracentrifugation and then subjected to size exclusion chromatography. Fluorescence analysis revealed that the chylomicron density fraction contains large amounts of chylomicron remnants.


Assuntos
Quilomícrons/sangue , Triglicerídeos/sangue , Vitamina A/análogos & derivados , Soluções Tampão , Cromatografia Líquida de Alta Pressão , Quilomícrons/química , Gorduras na Dieta/administração & dosagem , Diterpenos , Humanos , Lipoproteínas VLDL/sangue , Lipoproteínas VLDL/química , Masculino , Período Pós-Prandial , Ésteres de Retinil , Sensibilidade e Especificidade , Espectrometria de Fluorescência , Vitamina A/administração & dosagem , Vitamina A/sangue , Vitamina A/química
9.
Biochim Biophys Acta ; 1303(1): 22-30, 1996 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-8816849

RESUMO

The hepatic clearance of triglyceride-rich lipoproteins is mediated via apolipoprotein (apo) E which occurs in three common isoforms, apoE2, apoE3 and apoE4. To study the importance of the apoE isoforms on the response curves of different triglyceride-rich lipoproteins and the effect of chylomicron remnants on the composition of HDL, 37 normolipemics were investigated after a standardized fatty meal (8 apoE2/E2, 8 apoE2/E3, 8 apoE3/E3, 7 apoE3/E4 and 6 apoE4/E4). These individuals were matched for age, body mass index, fasting triglycerides, HDL-cholesterol, and apoA-I. A delayed chylomicron remnant clearance was observed only in apoE2 homozygotes, and this delay was neither correlated with fasting lip ds nor with peak lipoprotein concentrations. In apoE2/E3 heterozygotes, in contrast, the defective isoform E2 appears to be compensated for by the normal apoE isoform E3. In non-apo-E2/E2 individuals, the chylomicron remnant response was highly correlated with the magnitude of chylomicron and VLDL responses, with fasting triglycerides, and with the triglycerides enrichment and cholesterol depletion of HDL. These correlations were not observed in apoE2/E2. From these results we conclude that the chylomicron remnant response curve is an indicator of the extent of postprandial lipemia in non-apoE2/E2 individuals only.


Assuntos
Apolipoproteínas E/classificação , Quilomícrons/farmacocinética , Gorduras na Dieta/farmacocinética , Período Pós-Prandial/fisiologia , Triglicerídeos/farmacocinética , Adulto , Apolipoproteínas E/sangue , Área Sob a Curva , Jejum/sangue , Feminino , Humanos , Lipoproteínas HDL/química , Masculino , Taxa de Depuração Metabólica , Fenótipo , Retinoides/sangue
10.
Biochim Biophys Acta ; 1139(3): 196-202, 1992 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-1627657

RESUMO

Mitochondria isolated from male Wistar rats experimentally infected with the common liver fluke, Fasciola hepatica, exhibit loss of respiratory control from 2 weeks post-infection (Rule, et al. (1989) Biochem. J. 260, 517-523). We now report that subcutaneous injections of the anti-inflammatory drug, dexamethasone, during the final week of infection prevented the mitochondrial uncoupling and restored respiratory control almost to the levels of uninfected controls. Further investigations have shown that mitochondria from infected rat livers are unable to synthesize ATP and that abnormal respiration is also evident in hepatocytes isolated from infected rats. These abnormalities were absent when infected rats were treated with dexamethasone. In addition, liver mitochondrial function in infected, congenitally athymic, nude rats (CBH/R nu/nu) was not significantly different from that in uninfected nude or Wistar controls. These results provide evidence that the mitochondrial dysfunction in fascioliasis is host-mediated and that T lymphocytes in particular may be involved.


Assuntos
Dexametasona/farmacologia , Fasciolíase/metabolismo , Mitocôndrias Hepáticas/metabolismo , Trifosfato de Adenosina/biossíntese , Animais , Metabolismo Energético/efeitos dos fármacos , Fasciola hepatica , Fígado/parasitologia , Masculino , Ratos , Ratos Endogâmicos , Ratos Nus
11.
Arzneimittelforschung ; 42(1): 77-80, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1586386

RESUMO

Two recent reports showed a lowering of elevated lipoprotein(a) levels upon treatment with fish oil. The aim of this paper was to confirm this finding and to establish a dose-effect relationship. A double blind, placebo controlled cross-over study was carried out in 48 subjects with apolipoprotein(a) ("Apo(a)") values between 34 and 1062 U/l (median 387 U/l). The subjects were divided into 3 groups receiving 3.5, 7.1 and 10.6 g omega-3 fatty acids/day during 28 days. Parameters measured were blood levels of eicosapentaenoic acid ("EPA"), Apo(a) and fasting blood lipids. EPA levels rose in the three dosage groups by factors 7, 9 and 14, respectively, if compared to values upon placebo. Triglycerides were significantly lowered in a dose depending manner. Apo(a), however, was not changed. This held true for different baseline Apo(a) values and different fish oil dosages. It is concluded that fish oil treatment during 4 weeks cannot lower elevated Apo(a) levels.


Assuntos
Apolipoproteínas/sangue , Ácidos Graxos Ômega-3/farmacologia , Óleos de Peixe/farmacologia , Adulto , Apolipoproteínas A/metabolismo , Relação Dose-Resposta a Droga , Método Duplo-Cego , Ácido Eicosapentaenoico/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Triglicerídeos/sangue
12.
FEBS Lett ; 285(1): 94-6, 1991 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-2065786

RESUMO

Infection of rats with the liver fluke, Fasciola hepatica, impaired the responses of the perfused liver to calcium uptake and glucose release induced by the synergistic action of glucagon and vasopressin. Treatment of infected rats with dexamethasone prevented the impairment of each of these two responses.


Assuntos
Cálcio/metabolismo , Dexametasona/farmacologia , Fasciolíase/metabolismo , Glicogênio/metabolismo , Fígado/metabolismo , Animais , Sinergismo Farmacológico , Fasciola hepatica , Glucagon/farmacologia , Glucose/metabolismo , Fígado/efeitos dos fármacos , Masculino , Perfusão , Ratos , Ratos Endogâmicos , Vasopressinas/farmacologia
13.
Int J Parasitol ; 21(3): 353-55, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1894433

RESUMO

Respiration by mitochondria isolated from the livers of sheep following infection up to 15 weeks with F. hepatica was measured with the respiratory substrates pyruvate (plus malate) and succinate in the absence and presence of ADP; the rates were compared with those obtained by mitochondria isolated from livers of uninfected sheep. It was found that respiration supported by both substrates in mitochondria isolated from the left lobe but not the middle lobe of 4-week infected sheep exhibited abnormalities such that the acceptor control ratios were only marginally above one. Some, but not total, recovery was seen in the later stages of infection. The aberrant respiratory behaviour is similar to that observed with infected rats.


Assuntos
Fasciolíase/veterinária , Mitocôndrias Hepáticas/metabolismo , Consumo de Oxigênio , Doenças dos Ovinos/metabolismo , Animais , Fasciolíase/metabolismo , Ovinos
14.
Onderstepoort J Vet Res ; 57(1): 101-2, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2338993

RESUMO

Mycobacterium fortuitum was isolated from 3 species of freshwater fish in South Africa for the first time. The bacterium was isolated from oscars, guppies and discus fish from different sources. Heavy mortalities as a result of infection with this bacterium were reported from a guppy farm and the multi-resistance of this isolate to antimicrobials rules out the treatment of infected fish.


Assuntos
Doenças dos Peixes/microbiologia , Infecções por Mycobacterium não Tuberculosas/veterinária , Infecções por Mycobacterium/veterinária , Mycobacterium/isolamento & purificação , Micobactérias não Tuberculosas/isolamento & purificação , Animais , Peixes/microbiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , África do Sul
18.
Arzneimittelforschung ; 38(12): 1783-6, 1988 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-2854466

RESUMO

Omega-3-fatty acids are increasingly used by the selfmedicating patient. Since fish oils in capsules are regarded as dietary food, there are neither official regulations in the Federal Republic of Germany concerning a minimum content of omega-3-fatty acids nor detailed rules for the limitation of autoxidation of these highly reactive substances. Both fatty acid composition and the degree of lipid peroxidation were measured in this study in 23 OTC fish oil preparations. The proportion of omega-3-fatty acids was in most fish oils about 30%; exceptions were the only ethyl ester among the preparations with 59% and the cod liver oils (13% to 22%). Regarding the peroxide value considerable differences were found: the lowest was 2 and the highest was 44.7. Since lipid peroxides and their degradation products are basically toxic, a limitation of the allowed degree of lipid peroxidation in fish oils is strongly recommended.


Assuntos
Óleo de Fígado de Bacalhau/análise , Ácidos Graxos/análise , Óleos de Peixe/análise , Peróxidos Lipídicos/análise , Animais , Cromatografia Gasosa , Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/análise , Peixes
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